氯代纤维素的制备及其性质的研究

The preparation and properties of chlorodeoxylcellulose

本文用氯化锂／二甲基乙酰胺（LiCl/DMAc）作溶剂在均相条件下制备了氯代纤维素，研究了影响氯代反应速率的若干因素，讨论了产品的若干性质。研究发现，在氯代反应过程中存在两种取代反应，一个是氯原子取代，另一个是乙酰基取代。取代基的位置主要集中在葡萄糖基的第六位碳原子（C_6）上。纯的氯代纤维素仅溶解在DMAc中，而带有少量乙酰基的氯代纤维素则可以溶解在甲醇、乙醇、丙酮以及DMAc等溶剂中。在氯代纤维素的DSC曲线上有两个峰，一个是吸热峰，而另一个是放热峰。

The preparation of chloredeoxylcellulose in a hanogneous phase using LiCl/DMA as solvent was introduced. The influence of several important factors on the rate of chloronation and the poprties of the products were discussed. It was found that there were two substitution reaction proceeding during chlorination, one invdeed a chlorine atom, the other, an aceto-group. The positdri of the suhatituting group was mainly in the C6 of glucose. Pure chlorodeoxylcellulose disolved in DMA orily, but the product with a few ace tate groups could dissove in methanol, ethanol, acetone and DMA etc. The soubility increased with increasing content of acetate group in the products. there were two Peaks on the DSC curves of the products- one was endothendc, another was exothedric.